def print_models(unprinted_designs,completed_models):
    while unprinted_designs:
        current_design = unprinted_designs.pop()
        print("Printing mode:"+current_design)
        completed_models.append(current_design)
def show_completed_models(completed_models):
    print("\nThe following models have been printed")

    for completed_model in completed_models:
        print(completed_model)\

unprinted_designs = ["iphone case","robot pendant","dodecahedron"]
completed_models= []
print_models(unprinted_designs[:],completed_models)
show_completed_models(completed_models)
print(unprinted_designs)